Blankfort talks to Cockburn on day ISIS takes Tikrit. Cockburn speaks of ISIS in Syria, emerging from Al-Qaeda; of ineffectual Iraqi Shia government and army; marginalizing of Sunni; sees no end to Sunni-Shia conflict; negative influence of Saudi Wahabis; Iraq moving closer to division but splitting Baghdad problematic; how weapons sent to Islamists in Syria being used in Iraq; he speaks of inevitable resistance to foreign occupation; how explosive regional crisis resulted from US, UK actions.